OSHA 1926.51: what if my crew size changes mid-project?

Yes, you must order more portable toilets immediately when your crew size increases from 15 to 45 workers. The OSHA construction sanitation standard, OSHA 29 CFR 1926.51, requires one toilet for 20 or fewer workers. Once you cross 20 workers, the rule changes. For 20 to 199 workers, you need one toilet seat and one urinal per 40 workers.

Crew size drives unit count. Your new total of 45 workers puts you in the 20 to 199 range. The calculation is 45 workers divided by 40, which gives you 1.125. OSHA rounds up. You now need a minimum of two toilet seats and two urinals. Since a standard portable toilet counts as one seat, you must have at least two standard units on site. If you only have one unit from your original 15-worker crew, you need to order one more unit right away.

ADA compliance for clusters. If you place two or more units together, that forms a cluster. The ADA 5 percent cluster rule applies. At least one unit in that cluster must be an ADA-compliant portable toilet. Your rental company can swap a standard unit for an ADA unit when they deliver the new one.

Adjust service for the added use. More workers mean the holding tanks will fill faster. Your weekly service visit might need to increase to twice a week, especially in summer heat. Talk to your operator. A blocked truck access on service day means a missed service and a charge.

Order the unit now, confirm the ADA requirement, and update your service schedule. What's your ground condition and access for the new unit placement?